Electric reciprocatory device.



PATENTED AUG. 27, 1907.

J. B. RATHBUN. ELECTRIC REOIPROGATORY DEVICE.

APPLICATION FILED MAY 9.1906;

3 SHEETS-SHEET l.

No. 864,259. PATENTED AUG. 27,,190'7. J. B. RATHBUN.

ELECTRIC REGIPROGATORY DEVICE.

APPLICATION FILED MAY 9,1906.

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No. 864,259 PATENTED AUG. 27, 1907. J. B. RATHBUN.

ELECTRIC REOIPROGATORY DEVICE. APPLICATION FILED MAY9.1906.

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UNITED srrirns PATENT orsion.

JOHN B/RATHBUN, or nun/1on1), INDIANA, ASSIGNORTO onAnLss e. nrnewrnnorHAMMOND, INDIANA.

' ELECTRIC REGIFPRUGATORE DEVICE.

Epecification of Letters Eatent.

Patented rin at, 190?.

Application liled May 9, @906. Serial 110. 315,923.

To all whom it may concern:

Be it known that 1, JOHN B. RArnnUn, a citizen of I the United States,residing at Hammond, inthe county of Lake and State of Indiana,-haveinvented acertain new and usefullmprovement in Electric ReciprocatoryDevices, of which the following is aspecification.

vlviy invention relates to reciprocating devices and? ,Jcoils oi theseveral sets so as to actuatesaid set of coils and then in oppositedirections so that the magnetic effect of the coils on the core will beneutralized.

. The invention consists-further in providing suitable switching devicesfor so changing the direction of the currents, and further, in means ofrcausing such switch-, ing devices to act in accordance-with thepositionoi the core so that the energization and denergization (if themagnets will be automatically timed or synchro nized with the periodicmovements of the core.

The invention consists further in maintaining the energization of themagnetic devices during the whole or a very substantial part of theperiod ol'traveloi the view oi the tool fastening reciprocating part sothat gre'atiorce and high speed is obtainable from a comparatively smallamount of power. v

, The invention consists further in the several new and improveddevices, constructions and arrangements shown and described in thefollowing specification. The inventionhas been shown and will bedescribed as applied to an electric reciprocating hammer for-rivl etingor such like purposes, but it will be obvious that theapparatus showing.the connections,'soine oi the parts being here illustrateddiagrammatically, Fig. a, a view similar to Fig. .1 illustrating amodification, Fig. 5, a cross section on line 5-5 of 1, Fig. 8, aninverted plan view of a part of the coupling device, Fig. 7, a like viewoi a coupling nut, FigeS, adetail of one of the bridging rings, and Fig.9, a detail plan Lilre letters of reference indicate like parts in allthe drawings.

lshall first describe the mechanical features of a preferred form ofelectric hammer such as is shown in Figs. 1, 2 and 5 to 9 inclusive, andshall thendescribe the various switching arrangements, connections andthe like, so as to illustrate the operation of my apparatus as a whole,in this respect referring particularly to Figv 3.

A represents a reciprocating core of some magnetic material which worksin apipe or cylinder B preferably split or divided by the longitudinalgroove B to prevent the formation of induced'currents. Sfirrounding thiscylinder are the energizing magnets C, D, of the solenoid type, i'ormedon the removable spools O and D respectively. I have shown two of thesemagnets, but it will be obvious that there mightbe any number accordingto the exigencies of the :case; These magnets are composedicallyconsidered oi one of the magnets in the same direction and at thesame time causing currents to pass through the, coilsof the other magnetin opposite di- I lrections so as to. neutralize the magneticefiectinits j coils and lthen reversing this procedure as will be Idescribed in detail later.

'jSurrounding the coils O and 1D is a cylindrical casing E ofmagneticmaterial on the lower-end of which is secured the tool holder 13]. Ithas a central opening with. hardened steel bushing to receive the shankof the toel E The tool may he held in position bymeans Qf 'fl split ringE shown in detail in Fig. 5 which fits over a rib E on the tool and intoa groove formed by the ribs E E on the tool holder. These arrangementsmight, of conrse, be very greatly modified. The upper end of thecylinder E is screw threaded to receive the collafFE onto which isscrewed a nut E clamping together the fiangejoi cap piece E whichextends over the top of the cylinder B, and a flange on the hendle F.Apparatus of this sort will receive rather rough handling in thefoundries whe're'it is intended to be used and it is, therefore,desirable that the connection between the handle, which should beremovable and the body of the hammershould be very secure. I'havedesigned a form of union'which is very suitable for the purpose andwhich consists in forming a flange l). having the upturned edgeE on thecollar E and iorming ratchet' teeth E on the bottom of the nut Edesignedto operate with ratchet teeth E on the top or" the ring E held uagainst the nut by means of a spring Efinterposed be,-

each of a plurality of coils and means is provided zorenergiaing firstone and then the other of the magnets so as: to impart reciprocatory motion to the core; this being accomplished preferably by causing currents"to pass through-the coils magnetrot switching apparatus to be describedlater. When the core A, which has, of course, become a magnet throughthe energization of the adjacent solenoid G or D passes into one ofthese coils G or H, it will induce a current in the coil which isutilized in the switching apparatus, as will appear later. The severalcoils on the cylinder B are preferably separated by means ofrings ofmag.- netic material E separated by insulating pieces which shield theseveral coils from the fields of the adjacent coils. These rings willpreferably-be split or divided by the slots E, as is: clearly shown inFig. 8. I prefer to utilize the movement of the core for cooling thecoils. Td this end the cap piece E is provided with a centralpo rt E'and with the peripheral ports E which lead-to a space E between thecoils andthe cylinder E,. the cylinder being provided at th'e, side withthe I ports- E Below the magnet Hare the rings E 'and under partoi thehandle so that it will be closedwheii the handle is grasped. I- havehere-shownaninsulatingblock F set into the handle-and through which"ratus is shown in detail in the diagrammatic view, so

the wires F indicate only in a general way the connections leading'from'the switch. It will be understood that any desired form' of controllingswitch might be used. To the handle will-be preferably'connectedaflexible tube F to contain the conductors.

Itwill be observed that in this form of apparatus there is no switchingapparatus connected with the hammer except the hand manipulated pushbutton. All the more orless complicated switch mechanism necessaryioroperating the hammer is located outside and entirely apartfrom thehandle and may, in fact, be placed in a cabinet or-other safe placewhere it cannot be tampered'with or get out of order.

It has been found that in reciprocating-tools,particularly in hammers,where the reciprocatingpartis designed to give a blow to the shank of atool, thatthe end of a core is likely to become broken and spread withuse so as tb'stop the proper operation of the apparatus. To overcomethis I'provide the end oi my core A p and a variable resistance I inthis circuit. 0 D are wound in opposite directions and are con- =piecesM M M is an armature suitably supported by springsM M -with a part. ofrelatively soft material such as brass.

the core A, the solenoids C and D and the coils and ,H' are representeddiagrammatically. The solenoid O is shown as consisting ottwo coils'orwindings O and C The solenoid D also consists oi two windingsD and D Thearrangement illustrated contemplates connecting the coil 0 in serieswith the coil. D and the coil 0 in series withthe coil D Thecoils G andD are wound in the same direction or so connectedthat their 1 magneticresultant is the same. The coils C 'and D are wound in oppositedirections or so. connected that their magnetic resultant is opposite.It is evident this relation betweenthe series of coils might bereversed.

' A conductor 1 leads from one pole oi'the generator I to Conductor2-connects the coil D with the the coil 0 7 other pole of the generator;I have showna switch I The coils nectedwith the generator Icthroughswitching apparatus adapted 'to send the current first in one directionand then in the other througl'i such coils, and which switchingapparatus I will now' describe.

I is-a block ofinsulating material which carries on sidetwo'switchmembers I andJ connected together mechanically andelectrically by the binding .post'J andthetwo switch members J and J onthe other" side, connected: by the binding post 1. The 'block has-thestem J attached to a core J associated with anelectro-magnetic device.This electro-magnetic device consists of two solenoids K and L adaptedto move the core 1, back and'forth according to whether one or the otheris energized and with the core, to movethe switching -members away fromor against the contact screws J", J on one side and the contact screws-JJ on the other side, these screws passing through suitable terminalplates J and being preferably movable for-purposes oi adjustment.

1 The solenoid- L is operated through the agency of the coil G.

= This coil is located at theupper end i the travel of the core A sothat when thecore which-iaof course, mag netized throu h-the actionof-the energizing coils C C approaches theupper limitof its'travel itwill extend 'into the coil Gand induce thereina current of electricity.This current may be conducted by suitable plish this it may be made tooperate an electro-magnetic device, which in turnoperatesswitchingmechanism 'suitablyinterposed between a sourceofcurrent supply, such as the generator I, and the said solenoid; L. 'Ihave illustrated this arrangement in Fig. 3! ends of the coil G areconnected by conductors 3 -and 4 The with acoil M having a core M withprojecting pole on a bracket-M of insulating material and carrying theflexible switching arm M normally standing out of contact with thecontact screw M in a binding post M but adapted to be brought intocontact therewith when the coil M is energized. A conductor 5 leads fromconductor 1 to armature M aconductor 6 from binding post M to oneterminal ofsolenoid L, and conductor 7 from the other terminal ofsolenoid L to conductor 2. It will be seen, therefore, that when thecore A passes into the coil G the solenoid L receives current fromgenerator I and moves the switch, against the contact screws J JPrevious to this time the switch has been in contact with thecontact-screw J9, J A conductor 8 connects conductor 1 with bindingpost. J

and a conductor 9 connects conductor 2 with binding post J From thecontact screw J 'a conductor 10 leads to one terminal of the coil 0 theother terminal being connected with one terminal of the coil D byconductor 11. From the coil D a conductor 12 leads to a solenoid Nwhich, with a similar solenoid 0 controls acore N having astem Mconnected with the block J. This pair of solenoids is designed to holdthe switch in either one position or the other after it has been movedby solenoid K or L. Another conductor 13 leads from solenoid N to thecontact screw J which, as has been explained, is connected withconductor 1 .by conductor 8. Similarly coil His connected up with magnetM havingva core M with the pole piece extensions M M which will attractthe armature M carrying on this side the switch arm M cooperating withthe contact screw M mounted in the binding postM to close a circuitincluding solenoid K form d by a conductor 14 from binding-post M tosolenoid K, a conductor 15 from solenoid K to conductor 7, andconductors 1, 2, 5 and 7 already alluded to. A conductor 16 leads fromconductor 12 to solenoid O and a conductor 17 from this solenoid tocontact screw J A conductor 18 connects contact screw J 11 withconductor 10. Conductors 19 and 20 connect the ends of coil H with themagnetM.

In order to lessen sparking at the switch contacts, I prefer to includein my apparatus a condenser P which is here shown as connected up byconductor 21 with conductor 18 and by conductor 22 with conductor 17.When the switch has been moved against contact screws J .1 it is held bythe energization of solenoid O which is now in circuit with thegenerator through the conductors 16 and 17.

In order to illustrate the operation of my device, I will trace thecircuits through the apparatus for the various positions of theswitching devices. I shall first assume the core to be at the beginningof its upward travel. The circuit through coils G, D will be as follows:Generator 1, conductor 1, coil coil D conductor 2, resistance l fswitch1 back to the generator. This circuit will remain the same during thewhole operation of the device. The full line arrows indicate, for thesake of illustration, the direction of the current through coils C Dassuming the arrows to be associated with the turns of the wire on thefront side of the coil. The circuit through the coils C D will be asfollows: Conductors 1 and 8, binding post J, contact arm J contact screwJ conductor 13, solenoid N, conductor 12, coil D conductor 11, coilOflconductor 10, contact screw J switch arm J binding post J conductor 9to conductor 2, and then as above described. The current throughsolenoid N will hold the switch arms I, J firmly against the contactscrews J J It will be observed that the current through coils C and C isflowing in the same direction around the core A; As a result, of course,the core A will be caused to rise. At the same time the current throughthe coil D is flow ing in the direction opposite to'that of the'currentthrough coil D Assuming the current to be flowing through D from rightto left, as shown by the full line arrow used in connection with thiscoil, the current through coil D will be flowing from left to right asshown by the full line arrows associated in the drawings with this coil.The magnetic effect of these coils upon the core will, therefore, benullified. Coils C and C may or may not have the same number of turns,and likewise the coils D and D I have shown these coils in multipleratio, the larger number of turns, in the coils through which thedirection of the current is changed. This preferred construction tendsto lessen the sparking at the switch as a lighter current may be made topass through this circuit with equal magnetic effect on the core.

When the core passes into coil G, a current will be generated in thefollowing circuit: Coil G, conductor 3, magnet M, conductor 4 to coil G.Armature M will be attracted by magnet M, closing the circuit at M, M",this circuit being traced as follows: Conductors l and 5,

1 armature M switch arm M contact screw M binding post M conductor 6,solenoid L, and conductor 7 to conductor 2, and thence as beforedescribed. The current passing through solenoid L will energize the sameso that it will draw in core J pulling the switch away from contactscrews J J and against contact screws J J. The current through coils G Dwill remain the same, while that in coils C D will be reversed asfollows: Conductors 1 and 8, switch arm J contact screw J conductors 18and 10, coil C conductor 11, coil D conductors Hand 16, solenoid O,conductor 17, contact screw J switch arm J and conductor 9 to conductor2, and thence as before described. The current passing through solenoid0 will energize the same to hold the switch at its left hand position(Fig. 3). The current will now pass through coil G in teh directionindicated by the dotted line arrows, that is, it will flow around thecore from left to right, thus neutralizing the current through coil C.The current through coil D will also be reversed and will flow aroundthe coil in the direction shown by the dotted line arrows, that is, fromright to left thesame as the current through coil D The lower solenoidwill, therefore, be energized and will draw the core A downward, thismovement continuing until the core reaches the coil H when a currentwill be induced which will take the following course: Coil H, conductor19, magnet M", conductor 20 back to coil H. The energization of magnet Mwill cause the armature M to be attracted and will close a circuit at MM This circuit will be traced as follows: Gonductors 1 and 5, armatureM, switch arm M5 contact screw M binding post M, conductor 14, solenoidK, conductors 15, 7, and 2, and thence as above described. This willenergize solenoid K and move the switch to the position in which it isshown in Fig. 3. This will, of course, change the flow of the current incoils C D back to .the original direction.

It will be observed that by this arrangement only a portion of thecurrent necessary to energize the magnets in succession is handled bythe switch, the current energization of one of these magnetic devicesand the.

, deenergization of the other of them is accomplished automatically andby the core itself when it reaches a certain position at one or theother end of its excursion. Were a commutator used to accomplish theoperation of 1 5 the switch,it would be necessary that the commutator.

should'be timed so as to operate the switch just at the right moment..;If the movements of the switch and the 1 core were notfaccuratelysynchronized a considerable loss of power would obviously result. In myinvention the position of the core itself conditions the movement .ofthe switch. It will be observed further, that after ithe switch has beenmoved it is held or locked firmly against the contacts by the switchholding solenoids N, O.- 1 g It will be clear that it will not benecessary to make use of all the above described, devices andcombinations, but that some of the features which I have described asconstituting my preferred form of apparatus might, under certaincircumstances, be omitted or 30. others might be substituted intheirstead. For ex 7 ample, mechanical means for shifting the switchmight be substituted. for the electro-magnetic means previouslydescribed. I have shown such mechanical means in the modification ofFig." 4. This form of apparatus is similar in many respects to thedevice of Figs. 1 and 2 and I shall, therefore, confine the descriptionto modified features. The handle Q is associated with a cylindricalcasing Q which has a flange Q clamped by the nut E Lying over the top ofthe cylinders B and E isa cap piece Q having the air ports Q for coolingthe coils in the manner described in the other form'of apparatus. Onthis cap piece is the insulating block Q on which is mounted a suitablecasing R containing the solenoids R" and R which correspond to thesolenoids N and O of Fig. 3. Mounted on a ring R are the contact screwsR, R electrically connected with the binding posts R Within thesolenoids is a reciprocating hollow core R with which is connected ahollow stem R A rod R extends through the core and the stem and carrieson its lower end the guide plunger B which is received in a cylindricalbore R formed in the upper end of the core A. A perforated cap R islocated at the upper end of this bore. The rod R? carries the disk Itbetween which and the shoulder R formed at the upper end of the chamberin the core R is interposed a coil spring R". A

similar spring R is interposed between a nut R on the stem R and a nut Ron the upper end of rod R The switch consists of a block S carrying onone side the switch arms S, S connected by the binding post S and on theother side, the switch arms 8, S connected by the binding post SConnected with the ring R by suitable uprights S S is a ring S ofinsulating material carrying the contact screws 8*, S elec- 6'5 tricallyconnected respectively with thebinding posts senses S", S When the coreA reaches the upper end of its travel it will abut against the end ofrod R and push i the switch from the position shown in the drawings tothe upper position against contact screws 8", S The springs R and R willact as cushions to prevent injury to the mechanism. Similarly when thecore reaches the lower position the cap piece It will come against theguide plunger R and pull the switch to its lower position. The handlehas a push button switch similar to that shown in Fig. 1 consisting of apush button T, spring'T coptact T and contact T For purposes ofillustration I have shown the circuits as follows although it-will beunderstood that there might be considerable variation without departingfirom my invention: A conductor 23 leads to binding post U, a conductor24, from binding post U to one of the coils corresponding to'the coilsO, D of the diagrammatic view of Fig. 3, a conductor 25, from the otherof such coils to binding post U, a conductor 26, from U to contact T anda conductor 27, from contact T back to the source of currentsupply. Thecircuit through the coils in which-the direction of the current isconstant is thus completed when the push button T is pressedin.

A conductor 28 connects binding post U with binding post S a conductor29, contact screw R with solenoid R, a conductor 30, solenoid R with oneof the coils corresponding to the coils C D of the diagrammatic view, aconductor 31, the other of these coils with contact screw R", and aconductor 32, binding post S with binding post U This completes thecircuit through the coils corresponding to. the coils 0 D of thediagrammatic view when the switch is in its lower position, the holdingsolenoid R being included in the circuit. A conductor 33, not showncomplete, connects contact screw 8 with solenoid R a conductor 34,solenoid R with conductor 31, and a conductor 35, not shown complete,connects conductor 30 with contact screw S This completes the circuitthrough the coils corresponding to coils 0 D when the switch is'in itsupper position, this circuit including the solenoid R I wish it to beunderstood that I do not desire to be limited to the exact details ofconstruction shown and described for obvious modifications will occur toany person skilled in the art.

with an electro-magnetic device comprising a plurality ofcoils arrangedso that their fields are coincident and means for sending currents ofelectricity through said coils, first in the same direction and then inopposite directions so that the coils first reinforce each other intheir magnetic effect upon the core\and then neutralize each other.

2. In a reciprocating device the combination oi? a core with anelectro-magnetic device comprising a plurality of with anelectro-magnetic device comprising a plurality of coils arranged so thattheirfields are coincident and connected up with a common source ofdirect current and a pole changing device connected with one of the saidcoils whereby the current is made to flow first in the same direction inthe coils and then in opposite directions so season "that the coilsfirst reinforce each other then neutralize each other as to theirmagnetic eflfect upon the core.

ciprocable core, with an electro-magnetic device for imparting'motion tothe same, comprising an energizing coil, means for maintaining acontinuous current of electricity in said coil, :1 second coil,similarly placed with respect to the travel of the core, means forsending currents of electricity through the second coil alternately inopposite directions, and a device for automatically eflfecting suchreversal of current conditioned on the positio of said core. 4

6. In a reciprocating device,the combinationof a re ciprocable core,with an electromagnetic device for imparting motion to the same,comprising an energizing coil, means for maintaining a continuouscurrent of electricity in said coil, a second coil, and means forsending currents of electricity through the second coil alternately inopposite directions, said coils having a ditterent numbe of turns andbeing connected up in multiple. I

7. Ina reciprocating device, the combination of a reciprocable core,with two electro-magnets each composed of a plurality of coils, saidelectromagnets oppositely disposed with respect to the travel. of thecore, and means for causing energizing currents and neutralizingcurrents to pass in alternation through each of .said electroiiiagnefs.

8 In a reciprocating device, the combination of. a reciprocable core;with two coils at each end of the core,

means for causing currents of electricity to flow through the severalcoils, and means for intermittently reversing the current through onecoil at each end of the core.

9. In a reciprocating "device, the combination of a re-..

ciprocable core, with a pair of energizing coils -one at .ciprocablecore, with a plurality of coils in series and arranghdal'ong the travelof the core, a second series of coils associated with the firstmentioned coils, acommon source of electrical supply, said series ofcoils being arranged in multiple, and a switch device for intermittentlyreversing the current through the second series. of coils.

11. In a reciprocating device, the combination of a re .ciprocable core,with a plurality of coils in series and arranged along the travel of thecore, a second series of coils associated with the first mentionedcoils, a common source of electrical supply, said series of coils beingarranged in multiple, and 'a switch device for intermittently reversingthe current through the second series of coils, the coils of the secondseries having a greater number of turns than the several correspondingcoils of the first mentioned series.

12. In a reciprocating device, the combination of a reciprocable core,with a pair of coils, one at each end of the core, a secondpair of coilsassociated with the first pair and having a greater number of turns,' acommon source of electrical supply, the coils of each pair beingconnected in series and the pairs of coils being connected in multiple,and a switch device for intermittently reversing the cur rent throughthe second pair of coils.

13. In a reciprocating device, the combination ofa reciprocable core,with an electro-magnetic device to impart motion to the core, a switchdevice for causing said electromagnetic-device to be energized duringvsubstantially the entire period of travel of the core in each directionand electro magnetic means for synchronizing the movements of theswitchwith the reciprocations of the core.

14. In a reciprocating device, the combination of a re ciprocable core,with an electro-magnetic device, a source of current supply, aswltch-device for intermittently connecting the electro-magnetic devicewith the source of current supply, and a holding device for holding theswitch in its closed position.

15. In areciprocating device, the combination of a reciprocable core,with a plurality of energizing'coils to impart motion to the core'inopposite directions, a source of current supply, and a switch having amember adapted to be moved back and forth between contacts, in time withthe ,reciprocations of the core to intermittently reverse the currentthrough certain ofsaid coils.

16. In a reciprocating device, the combination of a reciprocable core,with a plurality of energizing coils to impart motion to the core inopposite directions, a source of current supply, a switch adapted tointermittently reverse the current through certain of said coils, and aholding device to hold the switch in its closed position.

17-. In a reciprocating device, the combination of a reciprocable core,with a plurality ofene'rgizing coils to impart motion to the core inopposite directions, a source 'of current supply and a switch, actuatedwhen the core has reached certainpositions in its travel in eitherdirection, adapted to intermittently reverse the current through certainof said coils. I

18. In a reciprocating device, the comulnation of a reciprocable core,with a plurality of energizing coils to impartmotion to the core inopposite directions, a source of current supply, and an electro-magneticswitch timed with the reciprocations of the core adapted tointermittently reverse thecurrent through certain of said coils.

, 19. In a reciprocating device, the combination of a reciprocabl core,with a plurality of energizing coils to impart motion to the core inopposite directions, aneurce -of current supply, an electromagneticswitch adapted to intermittently reverse the current through certain ofsaid coils, and means comprising a coil located on the travel of thecore for operating said switch.

2 0."In a reciprocating device, the combination of a reciprocable core,with a plurality of energizing coils to impart motion'to the core inoppositcdirections, a source of current supply, a switch adapted tointermittently reverse the current through certain of said coils, and anelectro-magnetic holding device to hold the switch inits closedpositions.

21. In a reciprocating device, the combination'or a reelectro-magneticcontrolling switch for said reciprocating means, and a device forenergizing the electro-magnetic controlling switch comprising a coil,and means conditioned on the position of the rcciprocable core forinducing a current of electricity in said coil.

23. In a reciprocating device, the combination of a re-' ciprocablecore, with an electro-magnetic device for imparting motion to the same,a controlling switch to control said electro-magnetic device, and meansfor operating said switch comprising a coil positioned with respect tothe reciprocable core so that a current of electricity is inducedtherein during a certain part of the travel of said core.

24. In a reciprocating device, the combinationof a reciprocable core,with energizing coils surrounding the same, a source of current supply,a device for controlling the supply of current to the coils, and meansfor operating said device comprising coils arranged at each end of theenergizing coils into which the reciprocable core passes.

25. In a reciprocating device, the combination of a reciprocable core,with energizing coils to impart motion to the same, a. source of currentsupply, an electro-magnetic controlling device, a coil into which thecore passes during a part of its excursion, and an electromagneticdevice connected with the coil and adapted, when'a current is induced insaid coil, to connect the controlling switch with the source of currentsupply.

26. In a reciprocating device, the combination of a recipro'cable .core,with electro-magnetic means for imparting motion to the core, a switchfor controlling the current to is brought into contact with the samewhen the core is reciprocated.

28. In a reciprocating device, the combination of a reciprocahle core,with means for imparting motion to the same, an outer casing, a handle,and means for connecting 20 the casing and handle comprising a flange onthe casing, a nut connecting the handle and the casing provided withratchet teeth, a ring having ratchet teeth to engage the ratchet teethof the nut, and an elastic device interposed between the ring and theflange.

JOHN B. RATH-BUN.

Witnesses:

A. H. CHEW, W. S. A'rwoon.

